Sanyo Chemical Industries, Ltd.

Seiko Epson Corporation

Hiroshi Odajima

Tomohisa Kato

Yuko Sugimoto

Eiji Iwawaki

Satoshi Utsui

Mana Sanpei

Takeshi Yano

Shinichi Naito

Kenji Kitada

Masaru Honda

Tsuyoshi Izumi

Masashi Minaki

Provided is an aqueous pigment dispersion having high initial dispersibility, high storage stability, and high color developability after printing, and particularly having high rub resistance (rubbing fastness) in cotton fabrics. An aqueous pigment dispersion for an aqueous inkjet ink, including a pigment and an aqueous medium, the pigment being dispersed with a polyurethane resin prepared by reacting an active hydrogen atom-containing component (A) with an organic polyisocyanate component (B), the active hydrogen atom-containing component (A) containing a polycarbonate polyol (a1), the organic polyisocyanate component (B) containing at least one compounds selected from the group consisting of aliphatic polyisocyanates (b1), alicyclic polyisocyanates (b2), and aromatic polyisocyanates (b3), wherein a coating film formed by drying the aqueous pigment dispersion at 50° C. for 12 hours has a storage modulus G' at 160° C. of 1 to 10 MPa.

Aqueous pigment dispersion

Provided is a toner binder which attains all of low-temperature fixing properties, gloss, and hot offset resistance and gives a toner that satisfies the flowability, high-temperature storability, charge stability, pulverizability, image strength, flex cracking resistance, and document anti-offset properties. The present invention is a toner binder which comprises a polyester resins and has a surfactant content of 100 ppm or less and in which the THF-insoluble components and the THF-soluble components respectively have a storage modulus (Pa) at 150&#xb0; C., G', and the storage modulus (Pa) at 150&#xb0; C., G&#x2032;, which satisfy the following relationships (1) and (2).&#x2265;10,000&#x2003;&#x2003;(1)&#x2265;500&#x2003;&#x2003;(2)

Toner binder and toner

The toner binder of the present invention contains a crystalline resin (A) and a resin (B) that is a polyester resin or its modified resin, the polyester resin being obtained by reaction of an alcohol component (X) and a carboxylic acid component (Y) as raw materials, wherein a temperature (Tp) of the top of an endothermic peak derived from the crystalline resin (A) as measured by a differential scanning calorimeter (DSC) is in the range of 40&#xb0; C. to 100&#xb0; C., and endothermic peak areas Sand Sduring heating satisfy the following equation.()&#xd7;100&#x2265;35&#x2003;&#x2003;(1)Sis an area of the endothermic peak derived from the crystalline resin (A) in the first heating process, and Sis an area of the endothermic peak derived from the crystalline resin (A) in the second heating process, when the toner binder is heated, cooled, and heated.

Toner binder, and toner

The toner binder of the present invention contains a crystalline resin (A) and a resin (B) that is a polyester resin or its modified resin, the polyester resin being obtained by reaction of an alcohol component (X) and a carboxylic acid component (Y) as raw materials, wherein a temperature (Tp) of the top of an endothermic peak derived from the crystalline resin (A) as measured by a differential scanning calorimeter (DSC) is in the range of 40&#xb0; C. to 100&#xb0; C., and endothermic peak areas Sand Sduring heating satisfy the following equation.()&#xd7;100&#x2267;35&#x2003;&#x2003;(1)Sis an area of the endothermic peak derived from the crystalline resin (A) in the first heating process, and Sis an area of the endothermic peak derived from the crystalline resin (A) in the second heating process, when the toner binder is heated, cooled, and heated.

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Kyoto, Japan

Hiroshi Odajima